This invention relates to the displacement of nuclear iodine substituents from an iodopyridine with gaseous chlorine.
The prior art suggests that the treatment of pyridine bearing nuclear iodine substituents with gaseous (molecular) chlorine does not displace the iodine substituents. British Pat. No. 259,960 teaches that nuclear iodine substituents on pyridines are not displaced by chlorine, but instead pyridyl iodochlorides are obtained.